A method for detecting insulation faults of high-voltage capacitive equipment

Abstract

The invention provides a high-voltage capacitive apparatus insulation fault detection method. According to the high-voltage capacitive apparatus insulation fault detection method, leakage current signals of at least four capacitive apparatuses connected to the same bus are selected as benchmarks for one another for calculating the dielectric loss of each capacitive apparatus; a lower dielectric loss value is subtracted from a higher dielectric loss value in every two capacitive apparatuses to obtain a relative dielectric loss value of each capacitive apparatus; then, by contrasting the changes in the relative dielectric loss values of the capacitive apparatuses, the diagnosis vector of a capacitive apparatus insulation fault is determined, the number of the capacitive apparatuses with the insulation fault is judged, and a fault diagnosis matrix is determined; finally, by contrasting the diagnosis vector with the built fault diagnosis matrix, the capacitive apparatuses with the insulation fault are located. The high-voltage capacitive apparatus insulation fault detection method not only can eliminate the interference caused by an external environment but also well solves the problem that a traditional relative measurement method may cover up the original ageing development tendency of the capacitive apparatuses, thereby effectively preventing the phenomenon of capacitive apparatus insulation fault missing detection from happening and ensuring the safety of equipment and workers in a transformer substation.

Description

Technical field [0001] The invention relates to a method for detecting whether there are insulation faults in a plurality of capacitive devices connected to the same busbar and accurately positioning the faulty devices, belonging to the technical field of detection. Background technique [0002] Capacitive equipment accounts for about 40% to 50% of the total equipment in substations and occupies an important position in substations. During the operation of capacitive equipment, its insulating medium is affected by a variety of factors such as heat, electricity, chemistry, and machinery, which will inevitably deteriorate, and in severe cases, it may lead to the loss of insulation. Insulation failure will not only affect the safe operation of the entire substation, but also may endanger the personal safety of other equipment and staff. In order to be able to grasp the operating conditions of capacitive equipment in time and prevent problems before they occur, it is necessary to mo...

AI Technical Summary

Problems solved by technology

Although the relative measurement method can overcome the shortcomings of the absolute measurement method, the existing relative measurement method generally obtains the relative dielectric loss by calculating the absolute value of the difference between the relative dielectric losses of two devices. The calculation formula is: , this calculation method may cover up the original aging development trend of the equipment, resulting in leakage monitoring of equipment insulation faults, so it is necessary to improve

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